WASHINGTON, June 14: Earth’s bigger, hotter planetary cousin may have been detected orbiting a star in our cosmic neighbourhood, astronomers said on Monday.
The most Earth-like of all 155 so-called extra-solar planets found orbiting stars besides our Sun, the newly unveiled planet is probably rocky like Earth, rather than big and gassy like Jupiter and most other extra-solar planets discovered in the past decade, the scientists said at a briefing.
“It took 150 observations of this star to glean the existence of this Earth-like planet,” said planet hunter Geoffrey Marcy of the University of California, Berkeley. “This will definitely be one of our favourite stars from now on.”
“It’s a very unearthly world,” said Jack Lissauer of NASA’s Ames Research Centre. “It’s likely to be the first rocky planet orbiting a star like our Sun.”
“It’s like Earth’s bigger cousin,” Paul Butler of the Carnegie Institution of Washington said in a statement accompanying the announcement. Mr Butler is a member of the team that found the planet.
The new planet is the smallest extra-solar planet ever detected, with about 7.5 times the Earth’s mass. Before this, the smallest planets found orbiting stars besides the Sun were at least 15 times Earth’s mass, making them more like distant, icy Neptune.
TOO HOT FOR LIFE: By contrast, this planet’s surface is far too hot — ranging from 204 to 371 C — to support life as it is known on Earth.
While Earth orbits the Sun at a distance of 150 million kilometres, this extra-solar planet almost hugs its star, orbiting about 3.2 million kilometres from the star Gliese 876 in the constellation Aquarius, just 15 light-years from Earth.
A light-year is about 10 trillion kilometres, the distance light travels in a year. In astronomical terms, 15 light-years is right around the corner.—Reuters
